Piston-ring construction.



C. E. JOHNSON.

PISTON RING 'consmucnou.

APPLICATION FILED DEC. 5, 1913.

Patented Feb. 22,1916.

Fist 3.

(June/whom C AQYIEQE. 7021119071 UNITED STATES PATENT OFFICE.

CHARLES E; JOHNSON, OF MUSKEGON, MICHIGAN.

PISTON-RING CONSTRUCTION.

Specification of Letters Patent.

Patented Feb. 22, 1916.

the piston ring construction in gas engines,

steam engines, compressors, pumps, &c. and its objects are, first, to provide a means whereby the inner ring will cause the outer rings to exercise an even and uniform pressure on all parts of the inner surface of the cylinder throughout its peripheral area as it travels longitudinally of the cylinder; second, to provide a means whereby the outer rings will be held in position so they I cannot creep revolubly on the inner ring and thus bring the partings in the outer rings together, or in conjunction with the parting 1n the inner ring and form an opening for the passage of steam or fgas through the rings to the opposite side 0 the piston, and, third, to provide a practically. un-

breakable inner ring for piston ring con struction.

I attain these objects by the mechanism and construction shqwn in the accompanyin drawing'in which Iigure 1 is a side elevation of the assembled rings forming one complete piston ring. Fig. *2 is anedge view of the same. F g. 3 is a face viewof the inner ringextended, and, Fig. 4 is an edge view of the same showing the approximate form of the ring before being a plied to the piston between the iston hea and the outer rings.

Similar letters; refer to similar parts throughout the several views.

In the construction of the inner ring I use a very high grade of flexible spring steel ribbon b, which is curved as necessaryfor various sized pistons, to avert the danger of uneven and improper pressure upon the outer rings, particularly at and near the ends of the rin With the ends of this ring left straig t, or upon the regular normal curve of the body of the r ng they would, when compressed to" place by the outer rings, in the piston construction, assume practicallythe formindicated by the-dotted lines in Fig. 1, and 'thus destroy the unity of pressure upon the outer rings to such an extent as to destroy the uniformity of pressure in the cylinder and thus render the action of the rings very undesirable; hence I find it necessary to curve the ends upon shorter radius and upon an lrregular curve, as indicated at f 7, so that when they are compressed within the outer rlngs 1n the piston construction an exact and uniform pressure will be exercised the entire length of the rings.

To avert the danger of the outer rings a a creeping on the inner ring, revolubly, and rendering it possible for the openings e e in the outer rings to come opposite each other, or of bringing them, or one of them over the opening 03 in the inner ring and thus: forming a passageway for gas, steam or other substance in the cylinder, I place two small pins in the inner ring, as indicated at 0 a, properly located to hold the several rings in proper relative positions to form and retain the desired laps in the ring construction.

It will be readily understood that with the several rings constructed and applied as hereinbefore described, it will be possible to use these improved piston rings until the outer rings a a are very nearly worn through, without any danger of leakage through or past the rings on the piston, as the great elasticity of the inner ring, and the even distribution of its expansive force or pressure upon the outer rings will cause the outer rings to bear uniformly around the inner surface of the cylinder throughout the entire area of their surfaces, thus insuring closefitting joints between'the inner ring and the outer rings,- and between the outer rings and the surface of the cylinder at all times. In this manner I am enabled to provide a piston ring that has far greater lasting qualities than could possibly be attained wlth an ordinary inelastic inner ring.

A, in Fig. 1, represents a cross section of a cylinder in which my rings are to be worked, entered for the urpose of showing the proper application of the rings.

What I claim as new, and desire to secure by Letters Patent-of the United States, is

1. In combination with a piston head and a cylinder, an assembled packing'ring consisting of two cast iron outer rings divided ata given point, in combination with an inner ring made of springsteel ribbon curved irregularly to a proper degree to insure a perfectly uniform pressure its entire length when compressed to a perfect annular form and confined Within the outer rings.

2. In combination With a cylinder and a piston therein, an assembled packing ring consisting of two cast iron outer rings machined to the exact diameter of the cylinder and open at a given point to allow of expansion, in combination With an inner ring made of spring steel ribbon curved irregularly to a proper form to be compressed to perfect annular form. and placed inside the outer rings and insure perfectly uniform pressure the entire diameter of the rings between the inner ring and the outer rings and between the outer rings and the surface of the cylinder, and pins projecting from the outer surface of the inner ring in position to pass into the openings in the outer rings to hold said several rings in exact relative position With each other.

Signed at Muskegon Michigan November CHARLES E. JOHNSON. In presence of GEORGE D. VANDERWERP, CHRIS SCHOUR. 

